Conventionally tubes are used in large quantities for the packaging and dispensing of various commodities, such as cosmetics, ointments, shampoo, toothpaste, ketchup, and the like. The tubes are usually made of plastic polymers as plastic polymers provides many advantages such as physical properties of strength, light weight, durability, non-toxicity, light and heat resistance, reusability, recyclability, inertness towards chemicals, etc. for packaging purposes. However, with increasing environment awareness and more hazards like non-degradation, toxic release over thermal decomposition, etc., attempts are being made to recycle plastic products.
Plastic recycling is a process of recovering scrap or waste plastic products such as bottles, tubes, etc., and re process the plastic to produce other products, usually different in form from their original state. For instance, soft drink bottles would be melted down and then recycled as carpet underlining various other polymers like PP or PE can be recycled and cast as plastic chairs and tables and other articles of household use. Typically a plastic is not recycled into the same type of plastic, and products made from recycled plastics are often not recyclable for the same form of the product.
The Society of the Plastics Industry (SPI) in 1988 developed a SPI resin identification coding system which comprises a set of symbols placed on plastic products to identify the polymer type. The SPI resin identification coding system facilitates efficient separation of different polymer types for recycling. The symbols used in the SPI resin identification coding system comprises of arrows that cycle clockwise to form a rounded triangle and encloses a number, often with an acronym representing the plastic below the triangle.
WO 2004/106173 discloses a multilayer bottle in which the outer and/or inner layers may be a blend such as metallocene polyethylene and high density polyethylene (HDPE) such as one component at about 25%/75% by wt. It is disclosed that the inner and/or outer layer may be virgin or the inner and/or outer layer(s) may include some recycled resin. One of such blend is MPE/HDPE. Another PCT publication WO 2005/063875 discloses a bottle fabricated from a single layer comprising a blend of metallocene polyethylene and a homopolymer high density polyethylene. This blend contains about 10% to 90% by weight metallocene polyethylene and about 10% to about 90% by weight a homopolymer high density polyethylene. The bottle may be a trilayer structure where the inner layer and/or outer layer may include some recycled resin. One of such candidate will be blend containing metallocene polyethylene (MPE) and HDPE.
U.S. Pat. No. 8,083,064 discloses a sustainable article substantially free of virgin petroleum-based compounds that includes a container, a cap, and a label, each made from renewable and/or recycled materials. The article has a shelf life of at least two years, and is itself entirely recyclable. The container can include polyethylene, polyethylene terephthalate, or polypropylene. The cap can include polypropylene or polyethylene. The label can include polyethylene, polyethylene terephthalate, polypropylene, or paper.
The above prior arts are incorporated in their entirety by reference herein.
There is a need in the art for a post consumer recycled HDPE polymer composition and product made up of such composition having a better toughness, brittleness properties, hot tack property, seal strength and ESCR properties.